Am I valid?

My husband and I have been married for over 3 years, we have 2 beautiful children and another on the way. A little over a year ago I found a few things on his phone that I didn’t like, for instance he told another random woman on Facebook she was the most beautiful woman he had ever seen, and he would message a girl “friend” all the time and say he loved her ( he’s the godfather of her children and I caught him sending money to her and paying for her daughters gymnastics, and she’s married to his friend). I brought it up to him and he broke down saying he has a porn addiction, not sure what this had to do with the situation at hand, but I brushed it off and asked him not to do it anymore because I know he wouldn’t like it if I said those things to another man. It’s been a little over a year now and I’ve noticed some changes, about 2 months ago he changed his password on his phone and I’ve recently been noticing changes in his behavior, he doesn’t call or text me as much as he used to, he always places his phone face down and when I’m around always has his phone turned away from me, he seems to be more distant and he’s not really ever home to help me with the kids. He has been working a lot of side jobs since before our second was born to make extra money to support us but it’s getting ridiculous, and I have noticed recently his lack of intimacy.

We have both been cheated on in our past relationships, but am I valid for thinking he’s hiding something from me? I’m scared to confront him and my worries become a reality.